Bump github.com/carabiner-dev/signer

Bumps [github.com/carabiner-dev/signer](https://github.com/carabiner-dev/signer) from 0.3.8-0.20260310160610-a37998585604 to 0.4.2.
- [Release notes](https://github.com/carabiner-dev/signer/releases)
- [Commits](https://github.com/carabiner-dev/signer/commits/v0.4.2)

---
updated-dependencies:
- dependency-name: github.com/carabiner-dev/signer
  dependency-version: 0.4.2
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

go.mod

@@ -5,7 +5,7 @@ go 1.25.8
 require (
 	github.com/carabiner-dev/attestation v0.2.1
 	github.com/carabiner-dev/collector v0.2.10-0.20260310234513-8d637f10649f
-	github.com/carabiner-dev/signer v0.3.8-0.20260310160610-a37998585604
+	github.com/carabiner-dev/signer v0.4.2
 	github.com/carabiner-dev/vcslocator v0.4.1
 	github.com/fatih/color v1.19.0
 	github.com/go-git/go-billy/v6 v6.0.0-20260226131633-45bd0956d66f

go.sum

@@ -105,8 +105,8 @@ github.com/carabiner-dev/policy v0.4.2 h1:5yMIqui603UgpUft6wwub7+sErgsCqUJuElZF/
 github.com/carabiner-dev/policy v0.4.2/go.mod h1:T7ruDEM6F7xWm6OzYRY9s+QiSMsh/VPDufZakCrlYOg=
 github.com/carabiner-dev/predicates v0.1.0 h1:t6tQF9gFdr6TIccWtuNk3kFasx8eu88INFVGkCUnjL4=
 github.com/carabiner-dev/predicates v0.1.0/go.mod h1:jL6EAD+LiI6GW/rOdRYAJF4HaA88/V2Q4n7yUGNQ7XM=
-github.com/carabiner-dev/signer v0.3.8-0.20260310160610-a37998585604 h1:2PeAzIFCqbCF/upSb4Hqj5HwTvuJ6D6KjP2F5yH7WrA=
-github.com/carabiner-dev/signer v0.3.8-0.20260310160610-a37998585604/go.mod h1:kqmUAFHKgQXFsIsIFjbk4UlOMXNte7J1IVxIgKAnY/M=
+github.com/carabiner-dev/signer v0.4.2 h1:VcrffuY8iHkKVcA91lyhOAg39u0V0fAdtQjSBYBrmcg=
+github.com/carabiner-dev/signer v0.4.2/go.mod h1:BTWxBXeVfqx23jLIQ72DIYAg105FjSwK11aAco5+ixo=
 github.com/carabiner-dev/vcslocator v0.4.1 h1:liMgw+UY012oiZx44hlKeVTdlJBMP2w9omPBQazmgaI=
 github.com/carabiner-dev/vcslocator v0.4.1/go.mod h1:8eVUuXkyIGemIIsbE7DY3ZWRrTYooO0By88Vhz084Ng=
 github.com/cenkalti/backoff/v4 v4.3.0 h1:MyRJ/UdXutAwSAT+s3wNd7MfTIcy71VQueUuFK343L8=